class ClsMethod:
    def __init__(self, a, b, c):
        self.__a = a
        self.__b = b
        self.__c = c

    #类方法的第一个参数必须是cls，代表当前方法属于当前的类
    @classmethod
    def is_valid(cls, a, b, c):
        return a + b > c and b + c > a and c + a > b


print(ClsMethod.is_valid(10, 9, 8))
